What people fail to understand is that they aren't talking about a perfect 1:1 pixel representation.
Do you understand:
1. online v. offline rendering; real-time v. pre-rendering
2. scanline rendering v. ray tracing
Avatar required a data-center because every pixel of every frame was drawn via ray tracing. If they used traditional methods of rendering a frame, it would have taken an order of magnitude less to achieve similar
results. It's simply a matter of pros and cons... Ray tracing is a lot simpler than restarization, but is far more latent.
Of course, I'm speaking as if Avatar had to be rendering online as opposed to offline.
In computer graphics, ray tracing is a technique for generating an image by tracing the path of light through pixels in an image plane and simulating the effects of its encounters with virtual objects. The technique is capable of producing a very high degree of visual realism, usually higher than that of typical scanline rendering methods, but at a greater computational cost. This makes ray tracing best suited for applications where the image can be rendered slowly ahead of time, such as in still images and film and television special effects, and more poorly suited for real-time applications like video games where speed is critical. Ray tracing is capable of simulating a wide variety of optical effects, such as reflection and refraction, scattering, and chromatic aberration.
The good news is that some developers are imagining their graphics engine as kind of a hybrid that uses ray tracing for reflections to maintian realism and scanline rendering/rasterization for geometry. Toms hardware has an article on it here
The claims are a bit sensationalist and honestly, it worked in causing you guys to react emotionally rather than with a logical rebuttal.
Most of you guys are PC thumpers so it's no surprise that when an article is posted here portraying consoles in a positive light you get emotional.